1. Field of the Invention
The present invention relates to an air-fuel ratio control system for internal combustion engines which is designed to control the air fuel-ratio of an engine to a predetermined value.
2. Description of the Prior Art
In a known type of fuel supply system for internal combustion engines, fuel is mixed with air in a carburetor in accordance with the load on an engine to thereby supply to the engine as optimum a mixture as possible. A disadvantage of this type of fuel supply system is that due to a delay in the response and the like, it is extremely difficult with this type of fuel supply system to operate the engine with an air-fuel ratio that is varied to suit the everchanging operating conditions of the engine and hence the effeciency of exhaust gas purification is extremely deteriorated.